706 Leading Edge Discriminator



The Model 706 is a 100 MHz Leading Edge Discriminator specifically designed for experiments with large counter arrays, offering high performance and reliability at a reasonable cost. The 706 features sixteen channels with common threshold and width controls. In addition, a fast veto input and a Bin Gate are common to all channels.

The 706 has high input sensitivity of -10mV variable to -1Volt via a 15-turn front panel control. A front panel test point provides a DC voltage equal to the actual threshold to insure accurate settings. Likewise, output durations are continuously variable via a front panel control over the range of 5nSec to 150nSec. The 706 employs non-updating regeneration circuits for output widths that are always the same duration regardless of the input rate conditions.

A fast veto input allows simultaneous inhibiting of all channels to reject unwanted events early in the system. Similarly, a bin gate will inhibit the entire module when applied via the rear connector.

The outputs are the current source type with one pair of negative bridged outputs for each channel. When only one output from the bridged pair is used, a double-amplitude NIM pulse (-32mA) is generated useful for driving long cables with narrow pulses. Two normal NIM levels are produced when both of the bridged outputs operate into 50 ohm loads. The output risetimes and falltimes are typically 1.5nSec, and their shapes are unaffected by the loading conditions of the other outputs.